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.Dd July 30, 2001
.Dt VM_PAGE_DONTNEED 9
.Os
.Sh NAME
.Nm vm_page_dontneed
.Nd "indicate that a page is not needed anymore"
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/vm_page.h
.Ft void
.Fn vm_page_dontneed "vm_page_t m"
.Sh DESCRIPTION
The
.Fn vm_page_dontneed
function advises the VM system that the given page is no longer
required.
If the page is already in the inactive queue or in the cache queue, this
function does nothing; otherwise the page is deactivated.
.Pp
Note that
.Fn vm_page_dontneed
does not necessarily deactivate a page, but instead implements an
algorithm that attempts to prevent small objects from having their
pages reused too quickly, and large objects from flushing smaller
ones from the queues as their pages are released.
.Sh SEE ALSO
.Xr vm_page_deactivate 9
.Sh AUTHORS
This manual page was written by
.An Chad David Aq Mt davidc@acns.ab.ca .
